1. Field of the Invention
The present invention relates to a door closer with a reliable arresting effect. In particular, the present invention relates to a door closer that may reliably arrest the door in a desired position and prevent injury to the user.
2. Description of the Related Art
FIGS. 1 and 2 of the drawings illustrate a conventional door closer comprising a cylinder 1xe2x80x2 having holes 10xe2x80x2 in an end thereof. Fasteners 101xe2x80x2 extend through the holes 10xe2x80x2 to fix the end of the cylinder 1xe2x80x2 to a doorframe. A piston rod 2xe2x80x2 is mounted in the cylinder 1xe2x80x2 and includes an end extending beyond the other end of the cylinder 1xe2x80x2. A retainer plate 3xe2x80x2 is mounted around an exposed section 21xe2x80x2 of the piston rod 2xe2x80x2. A fastener 211xe2x80x2 extends through a hole 210xe2x80x2 in the piston rod 2xe2x80x2 to fix the end of the piston rod 2xe2x80x2 to a door. The length of the exposed section 21xe2x80x2 in the open state of the door is longer than that in the closed state of the door. A compression spring 11xe2x80x2 mounted in the cylinder 1xe2x80x2 is compressed when the door is opened, and the spring force of the compression spring 11xe2x80x2 automatically closes the door when the force for opening the door vanishes. In a case that the door is to be retained in a desired open position so that the door would not be closed automatically, the retainer plate 3xe2x80x2 includes an arrestor 31xe2x80x2 for selectively pressing against a peripheral edge 12xe2x80x2 of the other end of the cylinder 1xe2x80x2. Thus, movement of the piston rod 2xe2x80x2 is stopped by an inner periphery 301xe2x80x2 defining a central hole 30xe2x80x2 of the retainer plate 31xe2x80x2. When automatic closing of the door is required again, the retainer plate 3xe2x80x2 is moved to disengage the arrestor 31xe2x80x2 from the peripheral edge 12xe2x80x2 of the cylinder 1xe2x80x2. When the force for opening the door vanishes, the returning force provided by the compression spring 11xe2x80x2 closes the door automatically. However, since the retainer plate 3xe2x80x2 is slidably mounted around the exposed section 21xe2x80x2 of the piston rod 2xe2x80x2, the retainer plate 3xe2x80x2 is apt to be shifted and thus fails to reliably arrest the door. In addition, the user could be injured by the unshielded retainer plate 3xe2x80x2 exposed outside the cylinder 1xe2x80x2.
An object of the present invention is to provide a door closer with a reliable arresting effect to reliably, precisely arrest the door in a desired open position and prevent injury to the user.
A door closer in accordance with the present invention comprises a cylinder and a piston rod mounted in the cylinder and having an exposed section outside the cylinder. A retainer plate, an elastic element, and an end cap are mounted around the exposed section of the piston rod. The retainer plate has a hole through which the exposed section of the piston rod extends. The retainer plate further has a push member extending beyond the end cap through a slot in the end cap. The elastic element is attached between the sleeve and the retainer plate. The push member is pushable toward the sleeve to cause an inner periphery defining the hole of the retainer plate engage with the piston rod such that a side of the retainer plate presses against the pressing rod to stop movement of the piston rod during closing of a door to which the door closer is attached.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.